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Re: [ARSCLIST] Magnetic Recording History (was OTR online?

For the record, the full name of AMPEX's founder is Alexander M. Poniatoff. It is my understanding that AMPEX came from Poniatoff's initials plus the first two letters of the word EXcellence.

At 03:27 AM 2009-01-02, Michael Biel wrote:

Second, that Hitler story is laughable. Hitler would "be" where ever the broadcast announcer said he was!!! Besides, Hitler was not making many speeches during the war. The sound quality of distant radio reception would mask any differences between a speech recorded on tape and a speech recorded on disc.

The version of this story that I heard was that Mullin and other Signal Corpsmen heard late night orchestra broadcasts of some length and thought that the sound quality was better than any long-form transcription device they had so they were interested in learning about this German technology after the war. They thought the recordings sounded live, but wondered if even Hitler would schedule musicians to play in the middle of the night.

I concur with Tony that early AM radio sounded much better than what we hear today. I recall owning a tube Zenith AM/FM radio that was reasonably high-fidelity in the 1950s--even on AM, and having my first exposure to the "Texaco Metropolitan Opera Radio Network" via WOR on the AM band.

Lastly, the entire first season of Philco Radio Time was recorded and edited on DISC. Tape was only used for mastering and editing starting in the second season, and even then the tapes were dubbed to disc for broadcast.

The first show recorded on tape was broadcast 1947-10-01 (which was the start of the 1947-1948 season). While the original tape went missing from the Ampex Collection prior to it being transferred to Stanford (it would be on a 14" Ampex NAB-hub reel in all likelihood), excellent 2nd generation copies remain. One of those has been digitized and delivered to the Stanford Ampex Collection.

No one at ABC wanted to risk going with tape live-to-air due to the fragility of the early tapes with multiple splices as well as having only two of Mullin's modified Magnetophons to play them on. Mullin shipped the transports and heads home but did not bother with the electronics as he saw improvements that he could make right away. Mullin's electronics have one additional tube as compared to the original AEG electronics with AC bias that he left behind.

At 10:51 AM 2009-01-02, Anthony Baldwin wrote:

In Germany this situation changed irrevocably in 1941 when AEG
engineers von Braunmühl and Weber stumbled across AC tape bias, where
the addition of an inaudible high-frequency tone resulted in a
striking improvement in sound quality ? something that was radical
enough to be discernible in prerecorded German AM broadcasts, if the
BBC's Caversham Park wartime monitoring reports are to be credited.

In fact, this is not so hard to believe, as the generous bandwidth of
national AM channels in the 1930s and '40s offered a far higher level
of AM fidelity than we're used to today. Nazi speeches aside, the
technical leap forward was most glaringly obvious in prerecorded
broadcasts by the likes of Fürtwängler and the Berlin Philharmonic,
as recent CD reissues have adequately confirmed.

For a more detailed discussion, please see
Engel, Friedrich Karl. <http://www.richardhess.com/tape/history/Engel--Walter_Weber_2006.pdf>Walter Weber's Technical Innovation at the Reichs-Rundfunk-Gesellschaft
Engel, Friedrich Karl and Peter Hammar, <http://www.richardhess.com/tape/history/Engel_Hammar--Magnetic_Tape_History.pdf>A Selected History of Magnetic Recording

There may be additional items of interest at http://www.richardhess.com/tape/history/

While Jack Mullen may have been able to kickstart Ampex by sending
home a couple of these liberated machines in bits via the no-doubt
bemused Army Post Office, the final broadcast requirement for tape ?
superior editability ? was only really achieved when the notoriously
fragile German acetate-backed "paper" tape could be abandoned in
1947-48 in favor of 3M's new, sturdier #111 stock. From that moment
on tape was definitely superior to disc as a studio medium, even if
Bing's transcriptions were still pressed up as discs.

That is partially true in that the German tape that Mullin brought back was fragile but more in the context that he had only about fifty reels (most of which survive in various states of repair in the Stanford Ampex Collection) and they were cut and spliced and recut and respliced until 3M came up to speed with tape manufacturing. Audio Devices also supplied some tape at this time or shortly thereafter (we found some spliced in with some of the German tape).

However, paper tape was abandoned circa 1935 in Germany while it was still made for the Brush Soundmirror and sold directly by 3M (Scotch) until some time in the 1950s in North America. Utah recorders in Canada also sold paper tape.

The German tape from 1935-1944 was an acetate-based tape called Magnetophonband Typ C. The factory where this was manufactured was destroyed in an industrial accident (not a war-related explosion) and from 1944 until the end of the war, only homogeneous PVC Magnetophonband Typ L tape was available. In the Typ L tape, the gamma ferric oxide was embedded in the PVC matrix and not coated on the basefilm like current and preceding tapes. The "Typ L" refers to IG Farben's trade name "Luvitherm" for their brand of PVC, just as "Mylar" became perhaps better known than PET for this later basefilm.

Most of the Magnetophonband tape has survived well. Some of the Typ C is starting to exhibit signs of vinegar syndrome, but this has occurred mostly with ones stored in the steel film-style cans than in the cardboard (press board?) boxes that most of them came in.

Some of the Typ L tape is showing some structural weakness and, as with many plastic films, shows a tendency to tear when edge nicks have occurred. Sometimes, splices would catch at the tape edge and start a long tear at a very shallow diagonal. In one case, the tear was about half a metre long. Repeated playing of this tape on the less-than-completely gentle original Magentophon in the Pavek collection has caused some pinholes to occur in the Typ L tape where clumps of the oxide material have fallen out of the PVC film matrix.

You may also enjoy reading my paper on the playback effort for some of these tapes. As of 2008-08, all of these have been delivered to both Stanford and the Pavek Museum and we included 101 (IIRC) different items in the collection, most were on the original Magnetophonband. These have been ingested into Stanford's Digital Repository system. I am not sure about access.
Hess, Richard L. <http://www.aes.org/journal/suppmat/hess_2001_7.pdf>The Jack Mullin/Bill Palmer Tape Restoration Project

Since there was additional material in the Pavek Museum collection, including Magnetophonband from other collectors, I concatenated the the Mullin-Palmer collection, the Mullin family collection, and the Pavek collection plus a few other related items into one collection for the sake of looking at these early tapes. The original material for the Mullin-Palmer collection resides at Stanford, while the Mullin family collection is retained by the family, and the Pavek retains its own collection. I have recorded the 1947-10-01 show back onto some new-old-stock Magentophonband Typ L for demonstrations at the Pavek and I need to make one or two more copies for them on NOS material I still have from the Pavek.



Richard L. Hess email: richard@xxxxxxxxxxxxxxx
Aurora, Ontario, Canada (905) 713 6733 1-877-TAPE-FIX
Detailed contact information: http://www.richardhess.com/tape/contact.htm
Quality tape transfers -- even from hard-to-play tapes.

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